Is it still okay to declare methods with prototype [closed]

I’m not a professional programmer and I used to write classes in JavaScript the old way like:

function Status(ctr, val, name) {
    this.ctr = ctr;
    this.val = val;
    this.name = name;
}


Status.prototype.init = function () {
    this.ctr.knopf.val(this.val);
}

The code works and performs okay for me, but Google keeps telling me I shouldn’t use ‘legacy code’. Is there any advantage to rewriting that code with classes? Will the code perform better?